John Gill Commentary Luke 20:23

"But he perceived their craftiness, and said unto them," — Luke 20:23 (ASV)

But he perceived their craftiness
Knowing what was in them, and being a discerner of the thoughts and intents of their hearts, he clearly saw that their view was either, that they might have a charge against him to the Roman governor, should he declare against payment of tribute; or that they might expose him to the people of the Jews, should he assert the lawfulness of it:

and said unto them, why tempt you me ?
with this ensnaring question.